Medium
E04 on Ravenheat TS 100

Your boiler is having trouble measuring the temperature of your tap water, which means it cannot heat your hot water correctly.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

Technical description

Domestic hot water (DHW) sensor damaged

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

E03View →E05View →

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